Oxford, UK, 6 February 2013 – Summit (AIM: SUMM), a drug discovery and development company advancing therapies for Duchenne Muscular Dystrophy (“DMD”) and C. difficile infections, announces that it has entered into a collaboration with Dr Yetrib Hathout from Children’s National Medical Center in Washington DC, for the development of utrophin biomarkers for DMD. The collaboration is being financially supported by a grant from the Foundation to Eradicate Duchenne and is part of a comprehensive biomarker programme being undertaken by Summit to advance its utrophin modulator programme for DMD. In late 2012, Summit reported that in a Phase 1 trial in healthy volunteers, its lead candidate SMT C1100 was safe and well-tolerated.

“We are delighted to be working with Dr Hathout on developing new biomarkers that will help advance our understanding of DMD while supporting the progress of Summit’s utrophin modulator programme,” commented Glyn Edwards, Chief Executive Officer of Summit. “Developing biomarker indicators capable of accurately measuring utrophin protein levels in muscle will be vital in helping to confirm the activity of our clinical candidate SMT C1100 in future patient trials. We thank the Foundation to Eradicate Duchenne for their continuing support in advancing this important medical research.”

Joel Wood, President of the Foundation to Eradicate Duchenne added, “We are committed to ensuring that urgently needed treatments have the best possible chance of successfully progressing through clinical trials. As such, we are pleased to provide funding to support Summit’s utrophin modulation programme, which is a novel and promising approach for treating all genetic forms of DMD.”

DMD is caused by genetic mutations that prevent patients from making the structural protein dystrophin, which leads to progressive muscle wasting and is ultimately fatal. Summit is pioneering utrophin modulation to stimulate production of utrophin, a functionally similar protein to dystrophin that is expressed in foetal and regenerating muscle, and which has the potential to restore and maintain healthy muscle function. This disease modifying approach would benefit all DMD patients, regardless of the underlying genetic fault causing their illness. SMT C1100 is the Company’s leading utrophin modulator drug and successfully completed a Phase 1 clinical trial in late 2012.

The development of new biomarkers that accurately quantify utrophin protein levels in DMD muscles will play an important role in providing evidence for the potential effectiveness of Summit’s utrophin modulator drugs in future patient clinical trials. Dr Hathout, a Principal Investigator at the Center for Genetic Medicine Research at Children’s National, will apply his expertise in cutting-edge proteomic techniques to develop a sensitive, robust mass-spectrometry based assay that can quantitatively measure utrophin protein levels in biopsies of DMD muscle. This collaboration is part of Summit’s comprehensive biomarker programme developing a range of assays that will measure biological endpoints to demonstrate muscle benefit after treatment with small molecule utrophin modulators.

About Children’s National Medical Center

Children's National Medical Center, located in Washington, DC, is a proven leader in the development of innovative new treatments for childhood illness and injury. Children’s has been serving the nation's children for more than 135 years. Children’s National is proudly ranked among the best pediatric hospitals in America by US News & WorldReport and the Leapfrog Group. For more information, visit www.childrensnational.org. Children’s Research Institute, the academic arm of Children’s National Medical Center, encompasses the translational, clinical, and community research efforts of the institution. Learn more about our research programs at www.childrensnational.org/research.

About Foundation to Eradicate Duchenne

The Foundation to Eradicate Duchenne Muscular Dystrophy (‘FED’) is a non-profit organisation founded in 2002 to provide funding into research for treatments and ultimately a cure for Duchenne Muscular Dystrophy (‘DMD’). THE FED raises money to support the world’s only clinical trials network for DMD. The clinical trials network is known as CINRG and works with scientists all over the world on therapies for DMD.

About Summit

Summit is an Oxford, UK based drug discovery and development Company targeting high-value areas of unmet medical need including Duchenne Muscular Dystrophy and C. difficile infection. Summit is listed on the AIM market of the London Stock Exchange and trades under the ticker symbol SUMM. Further information is available at www.summitplc.com.

For more information, please contact:

Summit

Glyn Edwards / Richard Pye

Tel: +44 (0)1235 443 951

Nomura Code Securities

(Nominated Adviser and Joint broker)

Chris Collins / Jonathan Senior / Giles Balleny

Tel: +44 (0)20 7776 1200

Hybridan LLP

(Joint broker)

Claire Louise Noyce / Deepak Reddy

Tel: +44 (0)207 947 4350

Peckwater PR

(Financial public relations, UK)

Tarquin Edwards

Tel: +44 (0)7879 458 364

tarquin.edwards@peckwaterpr.co.uk

MacDougall Biomedical Communications

(US media contact)

Michelle Avery

Tel: +1 781-235-3060

Forward Looking Statements

This document contains "forward-looking statements" within the meaning of the U.S. Private Securities Litigation Reform Act of 1995. Forward-looking statements can beidentified by words such as "anticipates", "intends", "plans", "seeks", "believes", "estimates", "expects" and similar references to future periods, or by the inclusion of forecasts or projections. Forward-looking statements are based on the Company's current expectations and assumptions regarding our business, the economy and other future conditions. Because forward-looking statements relate to the future, by their nature, they are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict. The Company's actual results may differ materially from those contemplated by the forward-looking statements. The Company cautions you therefore that you should not rely on any of these forward-looking statements as statements of historical fact or as guarantees or assurances of future performance. Important factors that could cause actual results to differ materially from those in the forward-looking statements and regional, national, global political, economic, business, competitive, market and regulatory conditions.